The present invention relates to a valve assembly which is located between a first fluid passage and a second fluid passage and which automatically interrupts or controls the flow of a fluid from the first passage to the second passage upon an abrupt increase of the fluid pressure in the latter beyond a normal level.
It is not unusual in everyday life to discharge water or other fluid from the free or outlet end of a hose pipe which has been elastically attached to a water supply faucet or other supply source. A major problem inherent in such a hose connection with a fluid supply source is that a blockage of fluid flow at any portion of the hose, such as would occur when it was unintentionally bent or pressed, develops an excessively high fluid pressure in that part of the hose upstream of the blocked portion to possibly break the hose or detach same from the supply source. An expedient to overcome this problem may comprise a pressure-resistive hose pipe, but this is not only a temporary solution but is costly as well.
An oject of the present invention is to provide an automatic valve assembly which obviates these drawbacks and assures a longer and safer usage of a hose pipe.
Another object of the present invention is to provide an automatic valve assembly which avoids reverse flow of a fluid from a second passage back into the first passage therethrough.
Still another object of the present invention is to provide an automatic valve assembly which permits the use of an ordinary inexpensive hose pipe.
In brief, an automatic valve assembly according to the present invention comprises a casing having a fluid inlet and a fluid outlet, a valve seat formed in the casing to divide the interior of the casing into a first chamber and a second chamber, a valve member engaged with the valve seat, a pressure chamber associated with said casing, a passage providing constant fluid communication between the pressure chamber and the second chamber, an actuating rod disposed between the pressure chamber and the valve member, and a means for biasing the valve member away from the valve seat through the actuating rod. The valve member is brought into engagement with the valve seat through the actuating rod in relation to the operation of pressure chamber when the fluid pressure inside the second chamber has been raised beyond a normal level.
It should be remembered that the fluid to which the valve assembly is applicable may comprise water or gas and the like fluids for instance.